Method of packaging using extruded net

ABSTRACT

Method of making multiple container carrier stock comprising strands of a resilient and deformable plastic material that has been extruded and fused in the molten or semi-molten state.

BACKGROUND OF THE INVENTION

This is a division of application Ser. No. 250,535 filed Mar. 5, 1972and a continuation of application Ser. No. 398,105, filed Sept. 17, 1973and now abandoned.

The invention can be made with known apparatus for extruding a moltenplastic material such as polyethylene from what may be described as aplurality of nozzles, and by then moving the nozzles or extruded strandswhile the plastic material is still in a molten or semi-molten state inreciprocating patterns along lines perpendicular to the direction ofextrusion to cause the strands to intersect and be fused at selectedpostiions linearly of the strands as they are extruded. The formedcarrier stock is then cooled and thereafter may be cut into individualcarriers. Suitable apparatus has previously been used to produce plasticnetting as shown in the patent to Mercer, No. 2,919,467, and as willappear hereinafter, the present invention contemplates the use of suchapparatus and variations thereof to produce the multiple containercarrier stock of the invention.

Prior art multiple container carriers have been made from plasticmaterials and particularly sheet material as shown for example in thePoupitch U.S. Pat. No. 2,874,835. Further, cord-like container carriershave been previously known as shown in the Poupitch U.S. Pat. No.3,097,740 and the Rockett U.S. Pat. No. 3,480,135.

SUMMARY OF THE INVENTION

The present invention is not concerned merely with the extrusion of aplastic material to form container carriers but is primarily directed tomultiple container carrier stock constructions which are easy to makeand which after severing into individual carriers will operate incooperation with a plurality of cans or bottles to hold the cans orbottles together as a unitary package for storage, handling andtransporting in a more positive and efficient way than heretofore knownin the art. The present invention further contemplates multiplecontainer carriers having substantially less material than containercarriers of comparable strength which are made from a sheet material.

In each of the embodiments of the invention, the plastic strands areextruded to have substantially the same cross sectional width andthickness.

The invention further contemplates carrier embodiments of asubstantially flattened configuration which are formed by passing theextruded carriers immediately after fusion between rollers. Ifnecessary, the rollers may be heated.

In a number of embodiments of the invention additional strands areextruded with or without movement of the extruding nozzles and fused tothe container encircling bands to provide integral handle means forcarrying a package of containers which are held together by the carrier.Such handle means may be of a different thickness than that of thecontainer encircling bands.

The individual container encircling bands are integrally connectedtogether with any number of other such bands to define a containercarrier stock. Generally, the extruded strands are severed betweentransversely arranged container encircling bands after the carrier stockhas been applied to a selected number of containers to form a unitarypackage of any selected number of containers. A common number ofcontainers for such a unitary package, especially in the beverageindustry, is a 6-pack.

The primary object of the invention is to provide efficient andeconomical multiple container constructions and arrangements utilizingknown extrusion apparatus capable of extruding and fusing a plurality ofmolten or semi-molten plastic strands.

Other objects and features of the invention will be apparent upon aperusal of the hereinafter following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of a section of extruded container carrierstock made according to the invention;

FIG. 2 is a top plan view of the extruded container carrier stock ofFIG. 1 as reformed in passing between a pair of rollers;

FIG. 3 is a top plan view of another embodiment of the invention;

FIG. 4 is a top plan view of the carrier stock of FIG. 3 and showing theresultant configuration of the carrier stock upon a portion of the stockbeing passed between a pair of rollers;

FIG. 5 is an elevational view, partially in cross section, showing aportion of the carrier stock of FIG. 4 as applied to a pair ofcontainers; and

FIG. 6 is a top plan view of another embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In all the embodiments of the invention, the strands as extruded fromthe extrusion nozzles are relatively uniform in cross sectional widthand thickness. That cross sectional shape may be round, square or mayeven have a compound shape such as D-shaped.

The preferred material of the invention is any suitable plastic materialthat can be extruded as strands which will in the molten or semimoltenstate fuse when the strands are brought together or caused to intersect.The preferred plastic material is further selected as one which issufficiently resilient and deformable at normal ambient temperatures toform suitable carrier devices. One such material presently commerciallyavailable is low density polyethylene. Other plastic materials which maybe used are listed in the Schultheiss U.S. Pat. No. 3,242,023.

In reductions to practice of the subject invention it has been foundthat the lines and planes of fusion between the strands of the carrierresult in a carrier construction having unexpected and importantadvantages over previously known carriers which have been punched orslit from sheet material. One unexpected result is that the fusionprocess produces joints between strands wherein the plastic materialbridges the joint in smooth curvilinear surfaces and avoids sharpcorners or notches. That unexpected result is important when oneconsiders the stretching of the container encircling bands in applyingthose bands about the containers intended for association with thecarrier. As is well known, most plastic materials have what is generallycalled low notch resistance. In other words, most plastic materials whencut or punched to produce a product will have a tendency to notch, andwhen stretched, will be relatively weak at such notches and consequentlyincrease the likelihood of tears or separation of the material at thenotches. However, the extruded carriers of the subject invention byhaving fused joints, uniquely and unexpectedly produce strong andeconomical carriers in relatively small cross sectional dimensions. Thelack of notches is further found in the embodiments of the subjectinvention where the extruded carrier stock is passed between heatedrollers to flatten the carrier stock to resemble carriers cut or punchedfrom sheet material.

Another advantage of the extruded and fused carriers of the subjectinvention is that different portions may be extruded in differentthicknesses to make the most efficient use of the material for theintended functions of the carrier with a minimum of material.

In FIG. 1 of the drawings, a section of container carrier stock madeaccording to the invention is shown in plan view. Four plastic strands10, 11, 12 and 13 are simultaneously extruded, and while in a molten orsemi-molten state are caused to intersect and to be brought intoside-by-side contact in a repeating pattern to produce the carrierstock. As is apparent in FIG. 1, the nozzles which extrude the strands10 and 12 are positioned in a spaced apart relationship and are causedto reciprocate substantially together along lines perpendicular to thedirection of extrusion of the strands. Strands 11 and 13 issue fromextrusion nozzles which are also positioned in a spaced apartrelationship and which move together in the same pattern which isgenerally oppositely from the pattern traced by the extrusion nozzlesfor the strands 10 and 12. As may be seen in FIG. 1, the strands 10 and12 are directed over the strands 11 and 13 to form the intersections 14and 15.

The embodiment of FIG. 1 is shown as a carrier stock for individualcarriers for six containers, but it is to be understood that theextrusion nozzles may be moved to produce carrier stock of individualcarriers for other numbers of containers. The end of each carrier in thestock is formed by having the extrusion nozzles cooperate to cause aside-by-side fusion of the strands in two groups, one group of strands10 and 11 and the other group of strands 12 and 13 to form the joints 16and 17. The joints 16 and 17 have a length sufficient to permit atransverse cutting of the joints 16 and 17 to separate an individualcarrier from the stock.

The carrier stock of FIG. 1 further includes joints 18 which are formedby a side-by-side fusion of strands 11 and 12. The six containerencircling bands formed by the four extruded and fused strands 10, 11,12 and 13 are stretched and applied about a group of six containers suchas cans to form a unitary package which is conveniently stored andtransported.

In FIG. 2 the container stock of FIG. 1 is shown as passed between apair of rollers, the top roller of which is shown at 20. If necessarythe rollers 20 may be heated. The rollers 20 will flatten the strands10, 11, 12 and 13, and the intersections thereof to produce the carrierstock configuration shown in FIG. 2 wherein the strand 10 becomes ribbon10a, the strand 11 becomes ribbon 11a, the strand 12 becomes ribbon 12a,the strand 13 becomes ribbon 13a, the joints 14 become the web portions14a, the joints 15 become the web portions 15a, the joints 16 and 17respectively become the web portions 16a and 17a, and the joints 18become the web portions 18a. The flattened carrier stock of FIG. 2 maybe severed transversely through web portions 16a and 17a to formindividual carriers for a group of containers such as six cans. When thecontainer encircling bands thereof are stretched and applied about thecircumferential surface of the cans, the container encircling bands willassume a substantially frustoconical shape with the inner periphery ofthe container encircling bands immediately below the chimes of the cansand above the outer periphery of the carrier. That frustoconical shapeis substantially shown in the previously noted Poupitch U.S. Pat. No.2,874,835.

FIG. 3 shows another embodiment of the invention and primarily differsfrom the embodiments of FIGS. 1 and 2 in the contemporaneous extrusionof a central handle member 30. Similarly to the above describedembodiments, four plastic strands 31, 32, 33 and 34 are extruded fromfour nozzles which are reciprocated along lines perpendicular to thedirection of extrusion of the plastic to cause appropriate fusedintersections and side-by-side fusing with the straight line extrudedhandle member 30 to form a plurality of pairs of transversely positionedand longitudinally extending pairs of container encircling bands. Thefused intersections of the strands 31 and 32 form joints 35. The fusedintersections of the strands 33 and 34 form the joints 36. The elongatedside-by-side fusing between the strands 31 and 32, and 33 and 34 formthe severable joints between individual carriers of the stock as shownat 37.

The fused joints 38 between the container encircling bands of each pairwith the handle member 30 complete the arrangement of the carrier stockas shown in FIG. 3. The container encircling bands of FIG. 3 aresubstantially elongated in the direction of extrusion so that when thecontainer encircling bands are applied about the outer surface ofcontainers such as cans 39 in FIG. 5, a shortening of the distancebetween adjacent joints 38 occurs which causes the handle portion 30 tofold upwardly into a convenient finger loop for carrying the package.The particular finger loop 30a of FIG. 5 result from a flattening of thecentral portion of the carrier stock as shown in FIG. 4.

FIG. 4 shows the carrier stock of FIG. 3 passing through a pair ofrollers, the upper one of which is shown at 40. The rollers 40 arerelatively narrow and span the central portion of the carrier stock toflatten portions of the strands 31, 32, 33 and 34 into flattenedportions 31a, 32a, 33a and 34a respectively. The web portions 41 are acombination of portions of two groups of strands, with one groupcomprising strands 30, 32 and 33 and the other group comprising strands30, 31 and 34. When the container encircling apertures are stretched andcircumferentially applied to containers such as containers 39, thecentral web portions 41 will assume a somewhat U-shaped configurationsuch as shown in FIG. 5 and the handle means or finger loops 30a willproject upwardly for convenient carrying of a unitary package of thecarrier and a plurality of containers. A feature of the carrierconstruction of FIG. 4 is the substantial container surface engaging andgripping area resulting from the formation of the webs 41. That surfacegripping arrangement produced by the webs 41 is greater than the surfacecontact produced by the unflattened portions of the container encirclingbands, and is concentrated in the region of the package where verticalseparating forces between the containers and the carrier are at amaximum when the package is transported by the finger loops 30a.

FIG. 6 shows a further embodiment of the invention in plan view andcomprises four strands 50, 51, 52 and 53 which are simultaneouslyextruded and moved in appropriate patterns to form intersections andconsequent fused joints 54 and 55, and to form side-by-side fused joints56 at the ends of the individual carriers in the carrier stock.

Two additional stationary extrusion nozzles are provided for extrudingthe strands 57 and 58. Strand 57 is directed into fusing engagement withthe outer marginal edge of strands 50 and 51 to respectively form joints60 and 61. Strand 58 is extruded to meet and fuse with the outermarginal edges of the container encircling bands formed by the strands52 and 53 to respectively form the joints 62 and 63.

The carrier stock of FIG. 6 further includes strands 64. Strand 64 isformed by a seventh extrusion nozzle which is periodically alternativelystationary and reciprocating. The nozzle which extrudes strand 64 iscaused to remain stationary when the nozzles for strands 50, 51, 52 and53 are forming joints 60 and 62 on the one side of joints 56 andcontinues to remain stationary through the formation of the joints 56and through the formation of the next joints 60, 62, or 61, 63. Thenozzle forming the strand 64 is caused to reciprocate, and thisreciprocation need not be in the plane of the nozzles forming the otherstrands, between the ending of one pair of joints 60, 61, through theformation of the joints 54 and 55, and to the beginning of the nextjoints 61, 63. When the nozzle forming the strand 64 is stationary theweb portions 65 are formed between the container encircling bands ofeach pair of container encircling bands. When the nozzle forming strand64 is caused to reciprocate the finger loops 66 are formed betweenadjacent web portions 65.

By virtue of the described arrangement of the carrier stock shown inFIG. 6, a minimum of shortening or change in pitch occurs when thecontainer encircling bands are stretched and applied about the surfaceof the containers intended to be associated therewith, the strands 57and 58 will form taut side rails for the unitary package of the carrierand the containers retained thereby. The finger loops 66 have a lengthsufficient to permit a person's finger to easily slip thereunder forconvenient carrying of the package.

It should be noted that when the individual carriers are severed fromthe carrier stock of FIG. 6 the strands 57, 64 and 58 must be cut inaddition to transverse severing of the joints 56. If desired, thestrands 57, 64 and 58 may each be cut at two positions close to thecontainer encircling apertures to avoid excessive projections of thesevered strands 57, 64 and 58 from the end of an individual carrier.

It should further be noted that the invention contemplates that thestrands 57, 64 and 58 may be extruded to have selectively greater orlesser thickness than the thickness of the strands 50, 51, 52 and 53.

Having described the invention, it is to be understood that changes canbe made in the described embodiments by one skilled in the art withinthe spirit and scope of the invention as defined in the claims.

I claim:
 1. A method of packaging including forming a multiple containercarrier stock capable of being severed transversely at certainlongitudinally spaced positions thereof to form successive individualmultiple container carriers and applying said carriers to containers,said method comprising the steps of extruding a pair of strands of aresilient and deformable plastic material in a state subject to beingfused together upon contact, moving said extruding strands together in acontiguous side-by-side relationship for a predetermined period of timeto fuse said strands together in contiguous side-by-side portionsthereof of such a length as is capable of being transversely severed toform common ends for successive carriers, thereafter moving saidextruding strands apart and together and crossing in a repeating patternand fusing said strands at intersections thereof to define a pluralityof integral bands each having an inner circumferential dimension lessthan outer circumferential dimensions of containers intended to beassociated therewith and sufficiently large to enable said bands to bestretched and circumferentially applied about said containers,thereafter repeating the step of moving said extruding strands togetherin a contiguous side-by-side relationship for a predetermined period oftime to fuse said strands together in a contiguous relationship of apredetermined length capable of being transversely severed to form thecommon ends of a pair of longitudinally adjacent individual multiplecontainer carriers in said stock, and thereafter sequentially repeatingthe steps of forming said bands and said side-by-side portions to formsaid carrier stock as a longitudinal series of individual multiplecontainer carriers interconnected by said side-by-side portions, andthereafter stretching and applying each of said bands circumferentiallyabout a set of containers and contemporaneously transversely severingsaid strands intermediate said side-by-side portions thereby formingsaid containers into packages.
 2. In a method of packaging as defined inclaim 1, the further step of passing at least a portion of said formedcarrier stock between rollers to flatten said strands.
 3. A method ofpackaging as defined in claim 1, comprising the further steps, prior tothe step of stretching and applying each of said bands circumferentiallyabout a container and contemporaneously severing said side-by-sideportions, of simultaneously extruding a second pair of strands by thesubstantially identical steps for moving and fusing the first pair ofstrands, and moving corresponding bands of said first and second pairsof strands together in a tangential fusing side-by-side relationship toform a carrier stock comprising transversely positioned pairs oflongitudinally extending integral bands.
 4. A method of packaging asdefined in claim 3, comprising the further step of passing said formedcarrier stock between rollers to flatten said strands.
 5. A method ofpackaging as defined in claim 1, comprising the further steps, prior tothe step of stretching and applying each of said bands circumferentiallyabout a container and contemporaneously severing said side-by-sideportions, of simultaneously extruding a second pair of strands bysubstantially the identical steps for moving and fusing said first pairof strands, the step of further simultaneously extruding a fifth strand,and moving one longitudinal side of the bands of said first and secondpairs of strands into a tangential fusing side-by-side relationship withand on opposite sides of said fifth strand to form a carrier stockcomprising transversely positioned pairs of longitudinally extendingbands having an integral central strand adapted to serve as a handlemember.
 6. A method of packaging as defined in claim 5, comprising thefurther step in the formation of said side-by-side portions andintersections of said strands, longitudinally positioning saidside-by-side portions and said intersections relative to said fifthstrand to cause portions of said fifth strand extending longitudinallybetween adjacent transverse pairs of said bands to have a length greaterthan center-to-center distances of said bands.
 7. A method of packagingas defined in claim 6, comprising the further steps, prior to the stepof stretching and applying each of said bands circumferentially about acontainer and contemporaneously severing said side-by-side portions, ofsimultaneously extruding a third pair of strands and directing saidthird pair of strands in tangential fusing relationship to said bands onopposite longitudinal sides of said carrier stock to form integral siderails on said carrier stock.
 8. A method of packaging as defined inclaim 7, comprising the further step of forming said strands so thatsaid third pair of strands will be taut when said bands arecircumferentially applied about said containers.